Insulating cap for bearing assembly

ABSTRACT

A bearing assembly is disclosed herein. The bearing assembly includes an outer bearing ring including at least one first connection element. The assembly also includes a cap defining an axial portion and at least one radial portion defining a cavity configured to receive the outer bearing ring. The cap includes at least one second connection element configured to mate with the at least one first connection element. The cap is formed from an electrically insulating material to prevent EDM.

FIELD OF INVENTION

The present disclosure is directed to a bearing assembly and is moreparticularly related to an insulating cap for a bearing assembly.

BACKGROUND

In automotive applications including axles, such as hybrid engines withe-axles, electrical current can be generated in running modes that leadsto electrical arcing, pitting, and/or other types of damage to bearings.There is a growing need to provide an electrically insulating solutionfor bearings assemblies that prevents electrical current from passingtherethrough. This type of insulation is desirable to protect bearingraceways and rolling elements from electrical discharge machining (EDM).Electrical insulation protection components are particularly importantin a wet automatic transmission fluid (ATF) lubricated environment.

Known electrical insulating arrangements for bearings may includecoatings or over-molded insulating layers. However, the processassociated with forming these coatings and insulating layers can belabor intensive and expensive.

Accordingly, it would be desirable to provide an electrically insulatingsolution for a bearing assembly that is economical and simple toinstall.

SUMMARY

A bearing assembly is disclosed herein. The bearing assembly includes anouter bearing ring having at least one first connection element, and acap having at least one second connection element configured to matewith the at least one first connection element. The cap is formed froman electrically insulating material to prevent EDM and otherwise avoidnegative effects by electrical current passing through the bearingassembly. In one aspect, the cap is formed from plastic.

The first and second connection elements can each comprise mating spiralscrews, in one aspect. In another aspect, the first connection elementcomprises an axial groove or rib, and the second connection elementcomprises a mating axial groove or rib.

The outer bearing ring can further comprise an additional firstconnection element, and the cap can further comprise an additionalsecond connection element. The additional first connection element canbe formed as a post or a receptacle on an axial end face of the outerbearing ring, and the additional second connection element can be formedas a mating post or receptacle on an axial end face of the cap.

The assembly can further comprise a face cover arranged on a first axialend of the outer bearing ring and the cap. The cap can contact an entireradially outer surface of the outer bearing ring and a second axial endof the outer bearing ring opposite from the face cover. The face covercan include a first face cover connection element and a second facecover connection element. The first face cover connection element isconfigured to engage with the cap and the second face cover connectionelement is configured to engage with the outer bearing ring. In oneaspect, the first face cover connection element includes a first one ofa tab or a groove, and the cap includes a second one of a tab or agroove configured to engage with the first face cover connectionelement. The second face cover connection element can include a firstone of a protrusion or a receptacle, and the outer bearing ring caninclude a second one of a protrusion or a receptacle configured toengage with the second face cover connection element.

The cap and the outer bearing ring can be configured to be attached toeach other via application of at least one of rotational force or axialforce to at least one of the cap or the outer bearing ring.

In one aspect, the cap is formed from: high heat polyamide, glass fiberreinforced polyphenylene sulphide, polyetheretherketone (PEEK), or acomposite resin of phenol and aldehyde.

Additional embodiments are disclosed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing Summary and the following Detailed Description will bebetter understood when read in conjunction with the appended drawings,which illustrate a preferred embodiment of the disclosure. In thedrawings:

FIG. 1A is an exploded perspective view of a bearing assembly accordingto one aspect.

FIG. 1B is a perspective view of the bearing assembly of FIG. 1A.

FIG. 1C is a cross-sectional view of the bearing assembly of FIGS. 1Aand 1B.

FIG. 1D is a cross-sectional view of a cap of the bearing assembly ofFIGS. 1A-1C.

FIG. 1E is a cross-sectional view of an outer bearing of the bearingassembly of FIGS. 1A-1D.

FIG. 1F is a cross-sectional view of the bearing assembly of FIGS. 1A-1Einstalled with a housing.

FIG. 2A is an exploded perspective view of a bearing assembly accordingto another aspect.

FIG. 2B is a magnified view of an interface between a face cover and acap of the bearing assembly of FIG. 2A.

FIG. 2C is a cross-sectional view along a first cross-section of thebearing assembly of FIGS. 2A and 2B.

FIG. 2D is a cross-sectional view along a second cross-section of thebearing assembly of FIGS. 2A-2C.

FIG. 3A is an exploded perspective view of a bearing assembly accordingto another aspect.

FIG. 3B is a cross-sectional view along a first cross-section of thebearing assembly of FIG. 3A.

FIG. 3C is a cross-sectional view along a second cross-section of thebearing assembly of FIG. 3A.

FIG. 3D is a rear view of the bearing assembly of FIGS. 3A-3C.

FIG. 4A is an exploded perspective view of a bearing assembly accordingto another aspect.

FIG. 4B is a magnified view of an interface between a face cover and acap of the bearing assembly of FIG. 4A.

FIG. 4C is a cross-sectional view along a first cross-section of thebearing assembly of FIGS. 4A and 4B.

FIG. 4D is a cross-sectional view along a second cross-section of thebearing assembly of FIGS. 4A-4C.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Certain terminology is used in the following description for convenienceonly and is not limiting. The words “front,” “rear,” “upper” and “lower”designate directions in the drawings to which reference is made. Thewords “inwardly” and “outwardly” refer to directions toward and awayfrom the parts referenced in the drawings. “Axially” refers to adirection along the axis of a shaft. A reference to a list of items thatare cited as “at least one of a, b, or c” (where a, b, and c representthe items being listed) means any single one of the items a, b, or c, orcombinations thereof. The terminology includes the words specificallynoted above, derivatives thereof and words of similar import.

A bearing assembly 10 is generally disclosed herein that includes a cap30. In one aspect, the cap 30 is an insulating cap that is configured toattach to at least one element of the bearing assembly 10. The cap 30 ispreferably configured to attach to an outer bearing ring 20. The bearingassembly 10 can include a plurality of rolling elements 12 and a cage 14configured to support and space the rolling elements 12.

Connection elements are generally provided between at least one of thecap, the outer bearing ring, and/or a face cover of the assembly. Theterm connection element is used herein to refer to any type ofstructure, profile, or element that is configured to be joined orattached to another element, i.e. another connection element. In oneaspect, the term connection element refers to threading or screw-likeprofiles or grooves formed on one or more components. The termconnection element is also used herein to refer to clips, snap-infeatures, or other interfaces between elements. For example, the termconnection element can refer to a structure configured to undergo briefelastic deformation to clip or otherwise attach to another element. Theterm connection element is also used herein to refer to a protrusion orpost and a mating pocket or receptacle that is dimensioned to receivethe protrusion or post. This engagement can provide an interference fit,in one aspect, to ensure a tight connection between two components.

In an alternative configuration, one of ordinary skill in the art wouldunderstand that the cap could be attached or connected to otherelements, such as the bearing cage, an inner bearing ring, a shaft, or ahousing.

Referring to FIGS. 1A-1F, the cap 30 can include an axial portion 32 andat least one radial portion 34 defining a cavity 36 configured toreceive the outer bearing ring 20.

The outer bearing ring 20 includes a first connection element 22 and thecap 30 includes a second connection element 38 configured to mate withthe first connection element 22. As shown in FIGS. 1A-1F, the firstconnection element 22 can be formed as at least one groove. In oneaspect, the first connection element 22 is formed as a plurality ofcircumferentially extending spiral grooves. One of ordinary skill in theart would understand that any one or more of the grooves disclosedherein can consist of one continuous groove or a plurality of grooves.The first connection element 22 can generally be formed as at least onegroove, recess, pocket, receptacle, or other element configured tomatingly engage with another component. The second connection element 38can be formed as a groove configured to mate with the groove of thefirst connection element 22. The second connection element 38 can beformed as a plurality of circumferentially extending spiral grooves. Thesecond connection element 38 can generally be formed as at least onegroove, recess, pocket, receptacle, or other element configured tomatingly engage with another component. In one aspect, the first andsecond connection elements 22, 38 are formed on respective radialsurfaces of the outer bearing ring 20 and the cap 30.

The spiral grooves of the first connection element 22 and the secondconnection element 38 can extend for an entire axial extent of arespective one of the outer bearing ring 20 and the cap 30.

In one aspect, the first connection element is formed as a pocket andthe second connection element is formed as a protrusion or projectionconfigured to be received in the pocket. Alternatively, the secondconnection element is formed as a pocket and the first connectionelement is formed as a protrusion or projection configured to bereceived in the pocket. In one aspect, the first and second connectionelements are formed on respective axial surfaces of the outer bearingring 20 and the cap 30.

In an installed state shown in FIG. 1F, a housing 60 is included and thecap 30 provides an insulated barrier between the outer bearing ring 20and the housing 60. Based on this arrangement, the cap 30 acts as aprotective element against EDM.

In one aspect, the cap 30 is formed from an electrically insulatingmaterial. The cap 30 can be formed from plastic. The cap 30 can beformed from high heat polyamide, such as PA46-GF30; glass fiberreinforced polyphenylene sulphide, such as PPS-GF40;polyetheretherketone (PEEK), such as PEEK-GF30; a composite resin ofphenol and aldehyde, such as phenolic plastic; or a composite material,such as G-10/FR-4 glass epoxy.

FIGS. 2A-2D illustrate another aspect of a bearing assembly 200 thatincludes an outer bearing ring 220, a cap 230, and a cover 250. As shownin FIGS. 2A-2D, the outer bearing ring 220 and the cap 230 both includeconnection elements on respective interfacing radial sides or surfaces.In one aspect, the connection elements are formed as spiralcircumferential grooves 222, 238 that are configured to mate with eachother.

The cover 250 can include two distinct types of connection elements, inone aspect. The cap 230 can further include at least one additionalconnection element 232 configured to mate with at least one firstconnection element 252 formed on the cover 250. The outer bearing ring220 can further include at least one additional connection element 224configured to mate with at least one second connection element 254formed on the cover 250.

In one aspect, the additional connection element 232 formed on the cap230 includes a plurality of grooves or pockets, and the first connectionelement 252 formed on the cover 250 includes a plurality of tabs orflanges. In one aspect, the additional connection element 232 is asnap-in groove and the first connection element 252 is a snap-in tab.One of ordinary skill in the art would understand that the cap 230 couldinclude a groove and the cover 250 could include a tab. The additionalconnection element 232 can be formed at an edge between an axial surfaceand a radial surface of the cap 230.

The additional connection element 224 formed on the outer bearing ring220 can include a plurality of pockets or receptacles, and the secondconnection element 254 formed on the cover 250 can include a pluralityof posts or studs dimensioned to be received within the plurality ofpockets or receptacles of the outer bearing ring 220. In one aspect,this connection is provided as an interference fit. The additionalconnection element 224 can be formed on an axial end face of the outerbearing ring 220. Likewise, the second connection element 254 on thecover 250 is also formed on an axial end face of the cover 250. One ofordinary skill in the art would understand that the location of theseconnection elements can vary. In one aspect, the posts or studs 254 canbe used to prevent rotation and reduce the risk of breaking the tab 252.

FIGS. 3A-3D illustrate another bearing assembly 300. As shown in FIGS.3A-3D, the outer bearing ring 320 can include at least one axial groove322 configured to engage with at least one axial rib 338 formed on thecap 330. In one aspect, the at least one axial groove 322 includes aplurality of grooves and the at least one axial rib 338 includes aplurality of ribs. One of ordinary skill in the art would understandthat alternatively, the cap 330 can include grooves and the outerbearing ring 320 can include ribs. In one aspect, the grooves 322 andribs 338 extend in a completely axial direction. The grooves 322 and theribs 338 are also considered connection elements, in one aspect.

As shown in FIGS. 3A-3D, the outer bearing ring 320 can further includeat least one additional connection element 324, and the cap 330 canfurther include at least one additional connection element 339. In oneaspect, the connection elements 324, 339 are defined on respective axialend surfaces of the outer bearing ring 320 and the cap 330.

In one aspect, the connection element 324 on the outer bearing ring 320is a receptacle or pocket, and the connection element 339 on the cap 330is a post or stud. The outer bearing ring 320 can include a plurality ofreceptacles or pockets 324, and the cap 330 includes a plurality ofposts or studs 339 dimensioned to be received within the receptacles orpockets 324 of the outer bearing ring 320. One of ordinary skill in theart would understand that alternatively, the outer bearing ring 320could include posts or studs, and the cap 330 could include receptaclesor pockets.

FIGS. 4A-4D illustrate another aspect of a bearing assembly 400. Asshown in these Figures, the cap 430 includes at least one firstconnection element 432 configured to engage with at least one firstconnection element 452 formed on the cover 450. At least one secondconnection element 454 on the cover 450 is configured to engage with atleast one first connection element 424 formed on the outer bearing ring420. In one aspect, the first connection element 432 on the cap 430includes a plurality of grooves or pockets, and the first connectionelement 452 formed on the cover 450 includes a plurality of tabs orflanges. The first connection element 424 formed on the outer bearingring 420 can include a plurality of pockets or receptacles and thesecond connection element 454 formed on the cover 450 can include aplurality of posts or studs dimensioned to be received within theplurality of pockets or receptacles of the outer bearing ring 420. Asshown in more detail in FIG. 4D, the cap 430 can include a secondconnection element 439 configured to engage with a second connectionelement 425 formed on the outer bearing ring 420. The second connectionelement 439 formed on the cap 430 can be formed as a plurality of postsor studs and the second connection element 425 formed on the outerbearing ring 420 can be formed as a pocket or receptacle dimensioned toreceive the posts or studs.

In one aspect, connections between the caps and the outer bearing ringsare achieved via a pre-formed mechanically-based fastening or attachmentarrangement. None of the arrangements require separate bonding materialsor heat application, such as heat shrinking techniques, to secure thecaps to the bearing rings. The caps disclosed herein are fully formed orpre-formed prior to engagement with the outer rings. Each of the capsdisclosed herein can be attached to other components in the bearingassembly using minimal manual effort, such as screwing one componentrelative to another, snapping in one part relative to another, orcircumferentially aligning connection elements and pressing thecomponents together. Other simple manual techniques can be used toattach or connect the cap relative to other components of the bearingassembly. In one aspect, the cap and the outer bearing ring areconfigured to be attached or connected to each other via application ofat least one of rotational force (i.e. for the configurations includingscrews of FIGS. 1A-2D) or axial force (i.e. for the snap-inconfiguration of FIGS. 3A-4D).

In one aspect, the cap surrounds an entire radially outer surface of theouter bearing ring, and also contacts an entire axial end face of theouter bearing ring. In one aspect, the cap only contacts one axial endface of the outer bearing ring. In another aspect, the cap can contactboth axial end faces of the outer bearing ring.

Having thus described the present embodiments in detail, it is to beappreciated and will be apparent to those skilled in the art that manyphysical changes, only a few of which are exemplified in the detaileddescription of the disclosure, could be made without altering theinventive concepts and principles embodied therein.

It is also to be appreciated that numerous embodiments incorporatingonly part of the preferred embodiment are possible which do not alter,with respect to those parts, the inventive concepts and principlesembodied therein.

The present embodiment and optional configurations are therefore to beconsidered in all respects as exemplary and/or illustrative and notrestrictive, the scope of the disclosure being indicated by the appendedclaims rather than by the foregoing description, and all alternateembodiments and changes to this embodiment which come within the meaningand range of equivalency of said claims are therefore to be embracedtherein.

LOG OF REFERENCE NUMERALS

bearing assembly 10

rolling elements 12

cage 14

outer bearing ring 20

first connection element 22

cap 30

axial portion 32

radial portion 34

cavity 36

second connection element 38

housing 60

bearing assembly 200

outer bearing ring 220

spiral circumferential grooves 222

additional connection element 224 on the outer bearing ring

cap 230

additional connection element 232 on the cap

spiral circumferential grooves 238

cover 250

first connection element 252 on the cover

second connection element 254 on the cover

bearing assembly 300

outer bearing ring 320

axial groove 322

connection element 324 on the outer bearing ring

cap 330

axial rib 338

connection element 339 on the cap

bearing assembly 400

outer bearing ring 420

first connection element 424 on the outer bearing ring

second connection element 425 on the outer bearing ring

cap 430

first connection element 432 on the cap

second connection element 439 on the cap

cover 450

first connection element 452 on the cover

second connection element 454 on the cover

What is claimed is:
 1. A bearing assembly comprising: an outer bearingring including at least one first connection element; and a capincluding an axial portion and at least one radial portion defining acavity configured to receive the outer bearing ring, the cap includingat least one second connection element configured to mate with the atleast one first connection element, wherein the cap is formed from anelectrically insulating material.
 2. The bearing assembly according toclaim 1, wherein the cap is formed from plastic.
 3. The bearing assemblyaccording to claim 1, wherein the at least one first and secondconnection elements comprise mating spiral screws.
 4. The bearingassembly according to claim 1, wherein the at least one first connectionelement comprises a first one of an axially extending groove or anaxially extending rib, and the at least one second connection elementcomprises a second one of an axially extending groove or an axiallyextending rib.
 5. The bearing assembly according to claim 4, wherein theouter bearing ring further comprises at least one additional firstconnection element, and the cap further comprises at least oneadditional second connection element, wherein the at least oneadditional first connection element is formed as a first one of a postor a receptacle on an axial end face of the outer bearing ring, and theat least one additional second connection element is formed as a secondone of a post or a receptacle on an axial end face of the cap.
 6. Thebearing assembly according to claim 1, further comprising a face coverarranged on a first axial end of the outer bearing ring and the cap. 7.The bearing assembly according to claim 6, wherein the cap contacts anentire radially outer surface of the outer bearing ring and a secondaxial end of the outer bearing ring opposite from the face cover.
 8. Thebearing assembly according to claim 6, wherein the face cover includesat least one first face cover connection element and at least one secondface cover connection element, wherein the at least one first face coverconnection element is configured to engage with the cap and the at leastone second face cover connection element is configured to engage withthe outer bearing ring.
 9. The bearing assembly according to claim 8,wherein the at least one first face cover connection element includes afirst one of a tab or a groove, and the cap includes a second one of atab or a groove configured to engage with the at least one first facecover connection element.
 10. The bearing assembly according to claim 8,wherein the at least one second face cover connection element includes afirst one of a protrusion or a receptacle, and the outer bearing ringincludes a second one of a protrusion or a receptacle configured toengage with the at least one second face cover connection element. 11.The bearing assembly according to claim 1, wherein the cap and the outerbearing ring are configured to be attached to each other via applicationof at least one of rotational force or axial force to at least one ofthe cap or the outer bearing ring.
 12. The bearing assembly according toclaim 1, wherein the cap surrounds an entire radially outer surface ofthe outer bearing ring.
 13. The bearing assembly according to claim 1,wherein the cap contacts an entire axial end face of the outer bearingring.
 14. The bearing assembly according to claim 1, wherein the cap isformed from: high heat polyamide, glass fiber reinforced polyphenylenesulphide, polyetheretherketone (PEEK), or a composite resin of phenoland aldehyde.
 15. A bearing assembly comprising: an outer bearing ringincluding at least one first connection element; and an electricallyinsulating cap defining a cavity configured to receive the outer bearingring, the cap including at least one second connection elementconfigured to mate with the at least one first connection element,wherein the cap and the outer bearing ring are configured to beconnected to each other via application of at least one of rotationalforce or axial force to at least one of the cap or the outer bearingring.
 16. The bearing assembly according to claim 15, wherein the atleast one first and second connection elements comprise mating spiralscrews, and the cap and the outer bearing ring are connected to eachother via application of rotational force to either the cap or the outerbearing ring.
 17. The bearing assembly according to claim 15, whereinthe at least one first connection element comprises a first one of anaxially extending groove or an axially extending rib, and the at leastone second connection element comprises a second one of an axiallyextending groove or an axially extending rib, wherein the cap and theouter bearing ring are connected to each other via application of axialforce to either the cap or the outer bearing ring.
 18. The bearingassembly according to claim 15, wherein the cap surrounds an entireradially outer surface of the outer bearing ring, and the cap contactsan entire axial end face of the outer bearing ring.
 19. The bearingassembly according to claim 15, further comprising a face cover arrangedon a first axial end of the outer bearing ring and the cap, wherein theface cover includes at least one first face cover connection element andat least one second face cover connection element, wherein the at leastone first face cover connection element is configured to engage with thecap and the at least one second face cover connection element isconfigured to engage with the outer bearing ring.
 20. The bearingassembly according to claim 19, wherein the at least one first facecover connection element includes a first one of a tab or a groove, andthe cap includes a second one of a tab or a groove configured to engagewith the at least one first face cover connection element, and whereinthe at least one second face cover connection element includes a firstone of a protrusion or a receptacle, and the outer bearing ring includesa second one of a protrusion or a receptacle configured to engage withthe at least one second face cover connection element.